Sight-glass.



E. A. KBLSEY.

SIGHT GLASS.

APPLICATION FILED Amm. 1914.

llllllllllllll Patented Mar. 2, 1915.

einem A. KELSEY, .or MOUNT velenosi, YORK, ASSIGNOB To Nemesi reliure@ TUBING COMPANY, F .NEW YORK, Y A CORORAQION QF NEW YORK- SIGHT-Grass.

Mannes.

T0 all whom t may concern Be it known that I, EDGAR A. KELSEY, a citizen `of the UnitedY States, residing at Mount Vernon,in the county of Westchester and State of New York, have invented certain new and useful Improvements in Sight- Glasses, of whichV the following'is a specisight .glass comprising usually a tubular body with a cylindrical annular flange is confined within a casing projecting from the frame or body of the apparatus, the interior of which is to be observed, and which glass is secured in place by any suitable glass.

means and provided with a packing interposed between its outer surface and the interior of the casing to prevent leaking from the interior of the device around the sight In practice, it has been found difficult to remove a glass .of this character from its casing after fit has been in position kany length of time, because the parts have been made with a tight lit and the packing under the influence of heat', pressure and the presence of oily vapors, tends to become disintegrated and to spread to the space between adjacent partsy and to cement the glass in position. In such construction it is also necessary to use a packing especially adapt- Y ed to lit within the casing and around the body of the glass.

The purpose of my invention is to obviate the diliiculties and overcome the disadvantages inherent in thew form of device above described, and to that end it consists briefly in the provision within the casing of a beveled seat against which there is adapted to be pressed a sight glass of peculiar form,

comprising a truncated spherical body, with one or two cylindrical extensions, a packing interposed between the spherical portion of the body and the interior of the casing, and

r a follower threaded into the casing and Specication of Letters Patent Patented llplar. 2, 1915,

adapted 'to impiega against the packing, thel glass itself loosely fitting within the casing :andthe follower .so that when the follower is withdrawn, the glass is adapted either to fall out by gravity or to readily be removed. And in order specifically to secure a proper seat for the spherical portion of the glass, such seat is made to terminate within the circumscribing cylinder of the spherical portion of the glass.

In the drawings, Figure l is an end elevation of a portion of an apparatus such as a sigh feed lubricator provided with a casing and sight glass embodying a preferred form of the invention; Fig. '2 is a transverse vertical section on the plane of the line 2 2 in Fig. l; Fig. 3 is a perspective of the sight glass; and Fig. 4 is a perspective of the follower.

In the drawings, 10 is the body or frame' of the device to be provided with the sighting elements. It is suitably apertured and the periphery of such apertures is preferably internally threaded to receive the casing indicated at 11, and which is externally` threaded at its inner end to fit within such aperture. The casing is of usual tubular form and is vprovided with an inturned annular flange 12 which is beveledV at 13 to form a seat for the rounded surface of the sight glass as will presently be described. The annular flange forms a second seat at 14 adapted to be engaged by a packing 15 resting against the same.

Arranged within the casing is the sight glass comprising a central body 16 made up of a truncated sphere and which body is provided with a cylindrical extension 17 on one side and a second cylindrical extension 18 on the other side.

.19 is a follower externally threaded to engage the internal threads of the casing and provided with an inwardly projecting annular flange adapted to press against the packing 15. The glass comprising the rounded body and cylindrical projections is made so as loosely to fit within the casing and the follower so that when the follower is withdrawn it will either fall out by lgravity or it can be readily removed without eHort. The beveled seat 13 of the casing is preferably made so that its outermost edge is within the limits of the circumscribing cylinder of the spherical portion of the y of preventing the creeping of edge of said flange, a sight glass arranged to fit against said beveled portion, and a packing ring adapted to lie against the flange and between said glass and the inner side of 15 the larger body and against the inner end of the smaller body.

In testimony whereof I aHiX my signature in presence of two witnesses.

EDGAR A. KELSEY.

Witnesses:

LEOPOLD KAssANDnY, ALBERT W. MORSE.

Gopies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' Washington, D. C. 

